Interstate 70 (I-70) is a part of the Interstate Highway System that runs from Cove Fort, Utah, to Woodlawn just outside of Baltimore, Maryland. In Maryland, the Interstate Highway runs 91.85 miles (147.82 km) from the Pennsylvania state line in Hancock east to the Interstate's eastern terminus at its junction with I-695. I-70 is the primary east–west Interstate in Maryland; the Interstate Highway connects Baltimore—and Washington, D.C., via I-270—with Western Maryland. The Interstate serves Frederick and Hagerstown directly and provides access to Cumberland via its junction with I-68 at Hancock. I-70 runs concurrently with its predecessor highway, U.S. Route 40 (US 40), from Hancock to Indian Springs in Washington County and from Frederick to West Friendship in Howard County.

Frederick County is located in Maryland, United States. As of the 2020 U.S. census, the population was 271,717. The county seat is Frederick.